ROME — Silvio Berlusconi’s top political aide resisted growing calls Tuesday to step down as interior minister over the botched deportation of the wife and 6-year-old daughter of a Kazakh dissident, a flap which has ratcheted up tensions in Italy’s fragile coalition government.

Interior Minister Angelino Alfano, facing a vote of nonconfidence Friday in the Senate, told lawmakers that neither he, Premier Enrico Letta nor the foreign minister had been told about Kazakhstan’s diplomats urging lower-level ministry officials to swiftly deport businessman Mukhtar Ablyazov’s family from their Rome home in May.

But he acknowledged that he should been informed by the underlings about the highly unusual insistence by the diplomats that Italian police launch a manhunt for Ablyazov and that Italy immediately expel his wife, Alma Shalabayeva, and the child.

Alfano promised a shake-up of top police and interior ministry offices, and the first heads have already rolled.

Earlier in the day, the head of his own cabinet at the ministry resigned, and Alfano told lawmakers that he had asked for the resignation of a top police official as part of a shake-up to ensure “it doesn’t happen ever again, so that a minister of whatever government would not be aware” of such an affair.

He said Italy, which revoked the expulsion order weeks after the woman and child had been hastily deported, was pressing Kazakhstan “so that their human rights aren’t violated, and they be free to return to Italy.”

Premier Letta’s center-left Democratic Party depends on the support of Berlusconi’s party, its main coalition partner. This week’s no-confidence motion will be a chance to see if the coalition is still sturdy or if it has frayed beyond repair.

Leaders from Letta’s party planned to discuss how they would vote on the non-confidence motion, which was sought by opposition legislators.

Meanwhile, a top leader of Berlusconi’s conservatives warned against any defections. The former premier’s People of Freedom party “and I hope the entire majority believe the interior minister’s words” and will back Alfano, said Renato Schifani, a top senator in the party.

But right-wing lawmakers — many of whom usually support Berlusconi’s forces — were unconvinced.

“The Shalabayeva affairs remains strange and surreal even after Minister Alfano’s speech,” said Guido Crosetto, in a statement. Crosetto, has often been a stalwart defender of Berlusconi’s forces, but he said the affair reeked of “negligence, mental laziness and approximations.”

Last week, Letta told Parliament the deportations shouldn’t have been ordered, and announced a probe of the matter. The woman and child, who had been living in Italy since September, were spirited to Kazakhstan on a government jet two months ago.

Alfano said an inquiry by the state police chief had found that diplomats from Kazakhstan’s embassy in Rome had described Ablyazov as a dangerous fugitive and a terrorist with ties to organized crime, but that they made no reference to his being a political dissident.

Ablyazov is widely said to have funded opposition parties and media in his homeland. Kazakhstan authorities want him on charges of siphoning off billions of dollars from BTA bank, based in Almaty, Kazakhstan. He has denied wrongdoing and called the allegations politically motivated. His whereabouts are unknown.

The interior minister said that the Kazakh diplomats urged police to search for Ablyazov in Rome, and that after they failed to find him, the diplomats demanded his wife and child be expelled.

Alfano said the woman had several opportunities, including with the assistance of a Russian-speaking Italian official, to tell police that her husband is a dissident and to ask for political asylum for herself and child, but that she never did so. Nor did she ever tell the Italian authorities that she and her daughter had permission to stay in Italy thanks to a residency permit issued by Latvia and valid for fellow European Union nations.

The minister contended that the deportation paperwork and procedures correctly followed the rules in the absence of knowledge about her husband’s status.

When the Kazakh diplomats were told that because there was no non-stop commercial flight from Rome to Almaty — the woman and child would have to change planes in Moscow — they argued there was a risk that Ablyazov’s supporters might stage a violent blitz to grab hold of the two during the stopover, and insisted the deportees be flown directly on a government jet, Alfano said.

Alfano called that circumstance yet another red flag that should have prompted interior ministry and police officials to report the situation to the minister himself. Italy’s state police fall under the jurisdiction of the Interior Ministry.

Letta’s office said the state police chief’s report confirmed that the “top levels of government weren’t involved” in the expulsions and that Foreign Minister Emma Bonino was summoning Kazakhstan’s ambassador in Rome “to receive proper clarification.”